As soft tissue adhesives, adhesives for wound dressing or wound dressings, various compositions, e.g., compositions containing cyanoacrylate and compositions using materials derived from organisms, such as compositions containing fibrin and compositions containing albumin, have been studied in the past (see, for example, patent literature 1 and patent literature 2).
The compositions containing cyanoacrylate are excellent in view of high adhesive strength, but they have poor biocompatibility, and there is a serious problem that formaldehyde generated by hydrolysis of cured products of the compositions exhibits high toxicity to organisms and inhibits healing. Particularly in parts that come into direct contact with central nervous system, blood vessels, etc., these compositions cannot be used. Moreover, since the curing time is extremely short, they are sometimes difficult to use.
The compositions containing materials derived from organisms are excellent in that the biocompatibility is high and healing is rarely inhibited, but they have low adhesive strength. Further, when the composition containing fibrin is used as an adhesive or the like, there is a side view that fibrin glue contained in the composition becomes a culture medium for bacteria, so that there is the risk of infection after operation or treatment and there is a fear of harmfulness.
When an adhesive is used for a wound of the skin or a soft tissue, or when a wound dressing is used for a wound, it is a usual way that the components are mixed in advance in a container or the like to prepare a composition and then the composition is applied to the surface of the soft tissue, the wound dressing part or the like, taking into consideration workability, prevention of infection, etc. However, the state of the composition after mixing sometimes has influence on the workability during the application of the composition, that is, for example, if the viscosity of the composition is too high, the composition is hard to apply, or if the viscosity is too low, the composition runs out of the necessary area. Moreover, if properties, such as elasticity and tensile elongation, of a film obtained by polymerization and solidification of the adhesive or the wound dressing are not proper, there sometimes occurs a problem that the film peels off from the skin after application because the skin or the soft tissue is a flexible adherend.
Since acrylic adhesives using an initiator containing an organoboron compound have low toxicity and low harmfulness and have high adhesive strength, development of them to dental applications has been promoted (see, for example, patent literature 3). However, if other medical applications, such as surgical applications, soft tissue adhesion applications and wound dressing applications, are intended, further improvement in handling stability or workability of the composition between mixing of the components and application to the application area has been sometimes required.